It's been two months since the release of Blender 2.65
, but now Blender 2.66 has surfaced and it incorporates a whole lot of new functionality.
Blender 2.66 introduces a dynamic topology sculpting mode, integration of Bullet Physics for rigid body simulation within the editor and animation system, UI and other usability improvements, support for hair rendering and other features in the Cycles Rendering, image transparency support, mesh modelling improvements, and an SPH particle fluid solver.
More details on changes to Blender 2.66 can be found from the Blender Wiki
. The release announcement on Blender 2.66 has yet to be issued but its source package can be downloaded from this directory